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<b>DB_SEQUENCE-&gt;open</b>
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<tt>
<b><pre>
#include &lt;db.h&gt;
<p>
int
DB_SEQUENCE-&gt;open(DB_SEQUENCE *seq, DB_TXN *txnid, DBT *key, u_int32_t flags);
<p>
int
DB_SEQUENCE-&gt;get_dbp(DB_SEQUENCE *seq, DB **dbp);
<p>
int
DB_SEQUENCE-&gt;get_key(DB_SEQUENCE *seq, DBT *key);
<p>
int
</pre></b>
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<b>Description: DB_SEQUENCE-&gt;open</b>
<p>The DB_SEQUENCE-&gt;open method opens the sequence represented by the <b>key</b>.
The key must be compatible with the underlying database specified in the
corresponding call to <a href="../api_c/seq_class.html">db_sequence_create</a>.</p>
<b>Parameters</b> <br>
 <b>key</b><ul compact><li>The <b>key</b> specifies which record in the database stores
the persistent sequence data.</ul>
 <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set to 0 or by bitwise inclusively <b>OR</b>'ing together one
or more of the following values:
<br>
<b><a name="DB_CREATE">DB_CREATE</a></b><ul compact><li>Create the sequence.  If the sequence does not already exist and the
DB_CREATE flag is not specified, the DB_SEQUENCE-&gt;open will fail.</ul>
<b><a name="DB_EXCL">DB_EXCL</a></b><ul compact><li>Return an error if the sequence already exists.  The <a href="../api_c/db_open.html#DB_EXCL">DB_EXCL</a>
flag is only meaningful when specified with the <a href="../api_c/env_open.html#DB_CREATE">DB_CREATE</a>
flag.</ul>
<b><a name="DB_THREAD">DB_THREAD</a></b><ul compact><li>Cause the <a href="../api_c/seq_class.html">DB_SEQUENCE</a> handle returned by DB_SEQUENCE-&gt;open to be
<i>free-threaded</i>; that is, usable by multiple threads within a
single address space.  Note that if multiple threads create multiple
sequences using the same database handle that handle must have been
opened specifying <a name="DB_THREAD">DB_THREAD</a>.</ul>
<br></ul>
 <b>txnid</b><ul compact><li>If the operation is part of an application-specified transaction, the
<b>txnid</b> parameter is a transaction handle returned from
<a href="../api_c/txn_begin.html">DB_ENV-&gt;txn_begin</a>; if the operation is part of a Berkeley DB Concurrent Data Store group, the
<b>txnid</b> parameter is a handle returned from
<a href="../api_c/env_cdsgroup_begin.html">DB_ENV-&gt;cdsgroup_begin</a>; otherwise NULL.
If no transaction handle is
specified, but the
operation occurs in a transactional
database,
the operation will be implicitly transaction protected.
Transactionally protected operations on a <a href="../api_c/seq_class.html">DB_SEQUENCE</a> handle
require the <a href="../api_c/seq_class.html">DB_SEQUENCE</a> handle itself be transactionally
protected during its open if the open creates the sequence.</ul>
<br>
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<b>Description: DB_SEQUENCE-&gt;get_dbp</b>
<p>The DB_SEQUENCE-&gt;get_dbp method returns the database handle.</p>
<b>Parameters</b> <br>
 <b>dbp</b><ul compact><li>The <b>dbp</b> parameter references memory into which
a pointer to the database handle is copied.</ul> 
<br>
<p>The DB_SEQUENCE-&gt;get_dbp method may be called at any time during the life of the
application.</p>
<p>The DB_SEQUENCE-&gt;get_dbp method
returns a non-zero error value on failure
and 0 on success.
</p>
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<b>Description: DB_SEQUENCE-&gt;get_key</b>
<p>The DB_SEQUENCE-&gt;get_key method returns the key for the sequence.</p>
<b>Parameters</b> <br>
 <b>key</b><ul compact><li>The <b>key</b> parameter references memory into which
a pointer to the key data is copied.</ul> 
<br>
<p>The DB_SEQUENCE-&gt;get_key method may be called at any time during the life of the
application.</p>
<p>The DB_SEQUENCE-&gt;get_key method
returns a non-zero error value on failure
and 0 on success.
</p>
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<br><b>Class</b>
<a href="../api_c/seq_class.html">DB_SEQUENCE</a>
<br><b>See Also</b>
<a href="../api_c/seq_list.html">Sequences and Related Methods</a>
</tt>
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